Roofing unit and method of making the same



Dec. 8, 1936 J. H. PLUNKETT 2,063,268

ROOFING UNIT AND METHOD OF MAKING THE SAME 1 Filed May 15, 1933 lid/675772 (707272 (Za k/4627 Patented .Dec. 8, 1936 Rooms. UNIT AND METHOD or MAKING THE SAME John H. Plunkett, Bronxville, N. E, assignor to The Patent and Licensing Corporation, New

York N. Y., a corporation of Massachusetts Application May 15, 1933, Serial No. 671,084

'1 Claims. (01. a -cs) This invention relates to an improved roofing element or the like, and a method of making the same. Asphaltic roofing units such as strip shingles are customarily made by saturating a sheet of felted fibrous material with asphalt,'coating the saturated sheet with an asphalt having a higher melting point so as to provide a waterproof coating on the face of the sheet, showering granular grit or other equivalent solid mate rial on the coating of asphalt while it is still hot and sticky so as to form' a protective surfacing layer. The shingles, shingle strips, or. other units are then cut from the sheet in the shape desired. These units are then ready to be laid-in courses on a roof. If desired, the shingles may be protected further by applying asphalt to the butt edges of the units so as to seal these edges against access of moisture to the fibrous constituents of the foundation, ends of which are exposed along. the cut edges of the roofing units.

It is an object of the present invention to provide roofing units which are suitably stifiened along the butt edges so that the tendency on the part of the exposed portions of the units to curl is resisted. To this end I apply an edge coating to the butt edges of asphaltic roofing unit, such edge coating being characterized by substantial inherent rigidity or stiffness when set. For this purpose I may employ a suitable soluble silicate such as potassium or sodium silicate with which I prefer to mix a quantity of pulverulent matter such as diatomaceous or infusorial earth. To this mixture may also be added suitable pigment or coloring matter. By using a soluble silicate as a binder for the mixture, I am able to regulate 4 at will the thickness'or viscosity of the mixture for convenient application thereof to the butt edges of roofing The application of a substantial film of such mixture to the butt edges 40 of roofing elements serves not only to seal the edges and to improve the weather resistance of the shingle but also to stiffen the marginal portions of the roofing elements which are exposed to the weather. When such a mixture is applied in liquid form to the edges of roofing units, it may be permitted to dry and set to a hard coating. If the roofing units are not to be laid for some time after they are made, the soluble silicate gradually becomes insoluble, possibly due to some reaction between the silicate and the infusorial earth which is mixed therewith. If, however, the roofing units.;"are desired for use soon after manufacture, the edge coating may be ren. dered immediately insoluble by the application of a suitable reagent such as ammonium chloride or ammonium sulphate. The hardened silicate, by reason of its inherent rigidity, imparts considerable stiffness to the roofing units and resists curling or bending of the weather corners thereof. 5

For a more complete understanding of the invention, reference maybe had to the following description and to the illustration on the drawing of which Figure 1 is a perspective view of a bundle of 10 strip shingles, showing spray pipes for the application of stifiening material to the edges of the shingles.

Figure2 is a fragmentary cross sectional view of the butt edge portion of a treated shingle 15 showing the stiffening edge coat on the butt edge.

The application of suitable material to the butt edges of strip shingles or the like for the purpose of stiffening the edge portions, may be facilitated 20 by collecting the shingles in bundles or stacks of suitable size, the edges being accurately registered so as to present practically plane surfaces on the sides of the bundles'formed by the edges of the individual units composing the bundles. 25

Figure I shows abundle of strip shingles H) of a conventional form, these shingles each having a plurality of shingle-simulating tabs ll spaced by suitable slots or cut-outs l2. As shown, a number of the strip shingles are collected together 30 in the form of a bundle, the edges of each of the shingles being flush with the edges of the other shingles in the bundle. Suitable material for stiffening the edges of the several shingles may be applied in any convenient manner as by 35 dipping or by a convenient number of spray nozzles IS, the number and arrangement of such nozzles being in accordance with which of the edges of the shingles are to be coated. In Fig ure 1, sufficient nozzles are shown for the coat- 40 ing of not only the butt edges but also both side edges of each of the strip shingles.

As indicated in Figure 2 the ,individual strip shingles may be of conventional structure including a felted fiber foundation 20 saturated with a 5 suitable grade of asphalt or its equivalent. This foundation may be covered on its weather face with a substantial coating 2| of waterproof naterial such'as blown or oxidized asphalt, a surfacing layer 22 'of granulated grit or other suitable material being partially embedded in the waterproof layer 2| and adhering thereto. The shingle may also be provided, if desired with a thin back coat 23 0f asphalt dusted with mica. According to the invention an edge coat 25 is ap- 55 plied to cover the butt edges of the shingles. The

cut edges in the slots l2 and also the side edges of the strip shingles may also be similarly coated. It is evident from Figure 2 that any tendency on the part of the roofing unit to curl from its plane would tend to bend the coating 25 edgewise rather than flatwise. Thus the inherent rigidity of the material itself is employed to the best advantage in establishing a substantial moment of resistance to bending stresses so as to oppose such curling tendency.

For coating material to form the edge coating 25, I preferably employ a mixture of diatomaceous or infusorial earth, silica, calcium carbonate, or an equivalent, with a soluble binder such as potassium or sodium silicate. These substances may be mixed in theproportion of onepart of silicate to two parts of infusorial earth. In addition, a suitable pigment may be included in the mixture to color the same. For example, red oxide may be employed for giving a red color to the mixture, other suitable pigments being employed for the production of other colors. The mixture is diluted, if necessary, to-facilitate the application thereof to the shingle edges either by means of spray nozzles or by a brush. If desired, the edges of the bundle of shingles may be dipped in a pool of such mixture. In brushing or spray: ing the mixture onto the butt edges of the shingles, the thickness of the film or coating applied to the shingles may to some extent be governed by the concentration or dilution of the mixture, a thinner mixture resulting in a thinner film or coating. The spraying may be of such a character as toform films of the mixture on edges of the several strip shingles in such a way that the films on each shingle will be substantially separate from the films on adjacent shingles. If preferred, the coating may be substantially continuous from one face of the bundle to the other so that the films on the individual shingles will be bonded to those on adjacent shingle edges. dried and set, is usually somewhat brittle, the treated shingles can readily be separated from one another by breaking the bonding films.

There appears to be a slow reaction between the diatomaceous earth and a soluble silicate of such a nature as to render the silicate insoluble after a considerable period of time. This insolubilizing process may be greatly accelerated by the use of a chemical reagent such-as a 10% solution of ammonium chloride or ammonium sulphate. Some such reagent may be sprayed onto the coated edge surfaces of the shingles at any Since the silicate, when time after the formation of such edge coating, and preferably as soon as the silicate coating is touch dry. Or, if desired, the silicate mixture and insolubilizing reagent may be sprayed on the edges of the shingles simultaneously so that the formation of an insoluble edge coating takes place almost immediately. The shingles are then ready for immediate use and can be broken apart from each other when desired for laying on a roof. I

It is evident that the invention herein described is capable of various modifications without departing from the spirit or scope thereof as defined by the following claims.

Iclaim:

1. A method of stiffening semi-flexible roofing units or the like, which comprises edge-coating the weather portion of each unit with a fluent mixture containing a silicate solution and pulverulent matter, and causing said edge coatings to set.

2. A method of stiffening semi-flexible roofing units or the like, which comprises edge-coating the weather portion of each unit with a coating mixture containing a silicate solution as a binder, and insolubilizing said binder.

3. A method of stifiening semi-flexible roofing units or the like, which comprises edge-coating the weather portion of each unit with'a coating mixture of pulverulent matter and a silicate solution, and treating the edge-coating with an insolubilizing reagent.

4. A method of stifl'ening semi-flexible roofing units or the like, which comprises edge-coating the weather portion of each unit with a fluent mixture of infusorial earth and a silicate solution, and insolubilizing'the coating by the appli-- cation of an ammonium salt in solution.

5. A semi -flexible roofing unit of the asphaltic type having a stiffening element on its weather edges consisting of an edge coating of an adhesive mixture of a silicate solution and pulverulent matter in the approximate ratio of one part to two, said mixture being in the form of a rigid mass.

JOHN H. PLUNKETI. 

